7Afe Injector Problem

[Delboy141184]

I started a thread in the carina section but since the avensis and carina share the same type of engine in some early avensis models i thought id post in here too as it would be relavant to the engine code and not actaully the car.(7afe)

I think ive got a faulty injector.seems to be a common fault from what ive read on net....

Its a 1995 1.8 petrol (7afe) ''lean burn'' carina with 125k miles,it has a itermitant missfire when hot and i think its injector number 3 thats causing the problem.the injectors are the blue cap ones.

When the missfire happens if i pull the conectors of injector number 1,2 and 4 one at a time then the missfire gets even worse which indicates those injectors are working fine however,when the missfire occurs and i pull the connector of injector number 3 the missfire stays exactly the same and the engine does not want to cut out/get worse or anything.

would this fault suggest it is injector number 3 thats causing me my problems???

i have no management light on and the car has been recently serviced and the problem just seems to lie with cylinder 3.

other symptoms when the missfire kicks in are.....hesitiation,loss of power,the car jerks alot under accelartion,high idle (which ive clead the throttle body and Idle control valve).other than this the car drives fine most of the time.

if anyone can shed a light on this before i start paying out for new/2nd hand injectors i would be very appreciative.

Cheers.

[Delboy141184]

anyone?

[igormus]

ok Mark

firstly in order to know what goes wrong you must to know construction of the injector in question.

Agree with you youve disclosed a faulty one. Now a bit of theory ->

The injector consists of : body; nozzle tip; control solenoid coil.

In order to evaluate performance --you have to uundo all four and have them tested on the calibrating stand where they must or musn't give an equal petrol portion per definite time. I presume you can start with calibration + an ultrasonic cleaning. this might be helpful to remove deposits clogging injection hole. In case this 3rd one will be proven as faulty -- the most like issue might be either with an injection hole clogging or control solenoid is near to die (burning out).

Regards / Igor